Stealth Rock should never be tested - it is not broken and I think we should be very very wary of testing bans.
I was under the impression Ho-oh was a "suspect" since Aeolus locked that rather long Ho-oh thread saying that it was a valid suspect, "so why not"?
I don't think Mew should be on that list. My stance on Mew is pretty much the same (although I don't think the wall breaking set is as dangerous I hyped up it to be on that thread). Also I think trick is the last of Mew's worries really and I don't think you really need to worry about Mew using Trick on a BP Set (I mean... think about it), especially when it already has
TAUNT to protect the BP Chain. Also your last "con" is literally "it has counters therefore it is not useful" which is a bit silly. I think you should "review" your pro/con list because I don't think it tells anything interesting. Also I don't think base 100 SpA is "good enough" for Specs without a good STAB Attack (this is important) to be considered a "good" choice user in this metagame - Psychic is a terrible attacking type this metagame really. Maybe I shall rewrite the choice items guide sometime.
Anyway, about Mew. The offensive stats aren't the issue - its more of the fact that it is unpredictable. This is a valid argument because this makes the Baton Passing set that much more effective, because the opponent has to take that much more of a risk before switching in. Even the Baton Passing set is "unpredictable" with its ability to pass any +2 boost it wishes (although I doubt anyone will be passing iron defense/amnesia anytime soon) - and especially I think its unique ability to pass +2 SpA OR +2 Attack is what makes it so risky for the opponent. add to this the fact that it is pretty much the best Wall Breaker in the Game - as apparent by just the Nasty Plot set. You're not going to be able to revenge kill it easily either considering its defenses, and it also has Explosion to take down one last thing before it goes. Add Taunt to the mix.
The issue isn't the fact that "Mew can be used well in any team", but "Mew can be used in any way on any team" and I think that's dangerous and what separates it from SR that "every team uses so well", because SR can only have "one effect". Platinum is unpredictable and to some nearly "unplayable" because of this and I think Mew is definitely something that will push it over the edge.
So I think the order should be
Latias - Latios - Manaphy - Ho-oh (if it is a valid suspect) - OHKO - Evasion Clause - Species Clause (This will be... interesting. Instinct tells me no but I think it will "work out" in the end unless everyone starts using Jump's Lucario allstar team) - UU Tiers
Also I was under the impression the Arceus issue was already decided - that "its not a Pokemon until Nintendo releases it")
See:
http://www.smogon.com/forums/showthread.php?t=47536